The present invention relates to medical sampling techniques and, in particular, it concerns a kit and corresponding method for obtaining a biological sample.
Many medical conditions may be diagnosed and/or monitored by performing various tests of samples of discharges. For example, analysis of vaginal discharges by various well documented tests is effective for diagnosis of sexually transmitted and other medical conditions including, but not limited to, infection by candida or chlamydia, trichomoniasis and bacterial vaginosis (BV). Tests of this type are typically performed on a sample taken during a clinical examination by a health care professional.
It has been proposed to perform tests of this type on discharges collected by an absorbent pad or the like used by the patient. An example of a system for performing tests on such samples is disclosed in co-assigned PCT Patent Application Publication No. WO 01/16576.
Use of vaginal secretions contained in an absorbent pad offers a number of advantages when compared to other methods of obtaining samples of the same secretion. For example, most patients are capable of deploying and removing such a pad without aid. This means that a sample can be obtained without a gynecological examination. In addition, a patient suspecting an infection could bring or send a pad containing a sample to her doctor, making a subsequent appointment to receive the results and a prescription for treatment, if so required. This reduces the number of necessary medical appointments, an advantage for both patient and doctor. In some situations, for example patients living in remote areas or patients desiring anonymity for the initial stages of diagnosis, a pad containing a sample could be mailed to a medical center, with results and possibly a prescription being returned by phone or fax.
Despite these advantages, implementation of testing systems for samples absorbed in absorbent pads present a number of practical problems. A first problem is to ensure a sufficient quantity and concentration of the sample to allow testing to be effective. In order to extract any and all samples from the entire area of a pad, large quantities of solvents would be required so that the resultant sample would be greatly over-diluted. This issue is addressed by the aforementioned PCT publication WO 01/16576 by use of an optical system to identify the exact location of a sample within the pad. A more difficult problem is that of deterioration of the sample during transit. Since the sample is typically secreted onto the pad and subsequently forwarded to a remote location for analysis, the sample is usually not fresh when tested. The combined effects of drying and oxidation due to atmospheric exposure render the sample unsuitable for use in many tests and may reduce the reliability of many others.
There is therefore a need for a kit and corresponding method for obtaining a biological sample by use of an absorbent pad and in a manner which preserves the sample, or even enhances it, for subsequent analysis at a remote location.
The present invention is kit and corresponding method for obtaining a biological sample.
According to the teachings of the present invention there is provided, a method for obtaining a biological sample of a discharge emitted from a portion of a body, the method comprising: (a) deploying an absorbent pad adjacent to the portion of the body for a period of time; (b) inserting at least a part of the absorbent pad into a sample chamber of a portable device; (c) adding sample extraction solution into the sample chamber; (d) sealing the sample chamber; and (e) transporting the portable device to a remote location for processing of the biological sample dissolved within the sample extraction solution.
According to a further feature of the present invention, the part of the absorbent pad is a sampling membrane configured to retain at least one biological material, the absorbent pad being configured to facilitate removal of the sampling membrane.
According to a further feature of the present invention, the portable device further includes a receptacle within which the sample extraction solution is stored prior to adding into the sample chamber.
According to a further feature of the present invention, the receptacle is implemented as an injector device, and wherein the step of scaling automatically actuates the injector device to perform the step of adding the sample extraction solution into the sample chamber.
According to a further feature of the present invention, at least one sample pre-processing agent is supplied within the sample chamber. The sample pre-processing agent preferably includes at least one nutrient for maintaining activity of a pathogen and/or at least one antibiotic agent. Preferably, the sample pre-processing agent is supplied in a solid form.
According to a further feature of the present invention, a disposable heating device is deployed to maintain the biological sample at a temperature above ambient temperature for a given time period.
According to a further feature of the present invention, a disposable cooling device is deployed to maintain the biological sample at a temperature below ambient temperature for a given time period.
There is also provided according to the teachings of the present invention, a portable device for use in generating a biological sample from a discharge emitted from a portion of a body onto a sheet of material, the device comprising: (a) a housing including: (i) a base portion formed with a sample chamber for receiving the sheet of material, and (ii) a lid portion configured for sealingly closing the sample chamber; and (b) an injector device associated with the housing and pre-charged with a quantity of sample extracting solution, the injector device being configured to be activated by closing of the lid portion to inject at least part of the quantity of sample extracting solution into the sample chamber.
According to a further feature of the present invention, the sample chamber is configured to have an open area of at least about 20 cm2 for insertion of the sheet of material.
According to a further feature of the present invention, the sample chamber is configured to have an enclosed volume when sealed of no more than about 5 cc, and preferably between 1.5 and 3 cc.
According to a further feature of the present invention, a major part of an enclosed volume of the sample chamber lies between a lower surface provided by the base portion and an upper surface provided by the lid portion, each of the lower and upper surfaces being formed with a plurality of projections projecting into the enclosed volume.
According to a further feature of the present invention, the lid portion is implemented with a top surface having a recessed portion, the injector device being deployed at least partially within the recessed portion.
According to a further feature of the present invention, the injector device is implemented as a syringe provided with a spring-loaded piston which is released by closing of the lid portion.
According to a further feature of the present invention, there is also provided a snap-lock configuration deployed to lock the lid portion closed against the base portion.
According to a further feature of the present invention, there is also provided a manually operable dispensing mechanism configured for dispensing a controlled quantity of liquid from the sample chamber.
According to a further feature of the present invention, the dispensing mechanism includes a finger-operable piston mechanism.
According to a further feature of the present invention, there is also provided a dropper aperture in fluid communication with the sample chamber for allowing release of liquid droplets from the sample chamber.
According to a further feature of the present invention, there is also provided (a) a removable sealing element deployed so as to seal the dropper aperture until immediately prior to dispensing of liquid from the sample chamber; and (b) a lock mechanism associated with the dispensing mechanism and configured to selectively prevent operation of the dispensing mechanism, the lock mechanism being mechanically linked to the removable sealing element so as to allow operation of the dispensing mechanism when the sealing element is removed.
There is also provided according to the teachings of the present invention, a kit for generating a biological sample from a discharge emitted from a portion of a body, the kit comprising: (a) an absorbent pad for deploying adjacent to the portion of the body, the pad including a sampling membrane configured to retain at least one biological material, the absorbent pad being configured to facilitate removal of the sampling membrane; and (b) a portable device including: (i) a housing having: (A) a base portion formed with a sample chamber for receiving the sampling membrane, and (B) a lid portion configured for sealingly closing the sample chamber; and (ii) an injector device associated with the housing and pre-charged with a quantity of sample extracting solution, the injector device being configured to be activated by closing of the lid portion to inject at least part of the quantity of sample extracting solution into the sample chamber.
According to a further feature of the present invention, the sampling membrane is configured for binding proteins.
According to a further feature of the present invention, the sampling membrane is associated with a frame located within, and withdrawable from, the absorbent pad.
According to a further feature of the present invention, the sampling membrane is associated with a handle configured to facilitate withdrawal of the sampling membrane from the absorbent pad.